I lived in one of UCL's more modern student apartment complexes. However, my unit consisted of a hallway with four single bedrooms off to one side, a bathroom off to the other side and a kitchen at the very end of the hall. The rooms were decent in size, considering that they are located in a city, however there was no comfortable common space and my flatmates and I were often frustrated with the absence of a living room type space.
Ideally, if I were to do it again, I would get a private apartment. Yet, the only drawback to this is that apartments in London are way expensive and the chances that one will find non-Americans to flat-hunt with, shortly after one's arrival, are pretty much slim to none.
Furthermore, I strongly suggest that if one wants to meet and hang out with the English/non-Americans during the year, DO NOT SHARE HOUSING WITH A BUNCH OF AMERICANS! Whereas, I continue to return to London to visit with all of the English and European friends that I met through my housing situation and friends of flatmates, etc, all of the Americans that I knew who lived with other Americans, only hung out with Americans and never made any lasting friendships with the English/Europeans.